The Democratic National Committee sued the Russian government, the Trump campaign and WikiLeaks on Friday, accusing them of a wide-ranging conspiracy to interfere in the 2016 presidential election to defeat Democrat Hillary Clinton.

The lawsuit alleges the defendants conspired before the election to hack into the DNC’s computer network and strategically leak the stolen information to bolster Donald Trump’s chances of winning the election. The conspiracy sought to undermine Mrs. Clinton’s campaign because Mr. Trump’s presidency...